How did the struggle between the US and USSR in the post WWII era lead to the Cold War?

In the time immediately after the end of World War II, the US and the USSR were jockeying for influence around the globe. This process actually began in the last days of the war as the Soviets tried to take more territory in Korea and, they hoped, Japan. The process went on in Eastern Europe as well. There, the Soviets started putting communist governments in place without the elections that they had agreed to hold. In the meantime, the US was acting as well. It announced the Truman Doctrine, promising to try to halt the spread of communism. The US also coordinated with France and Britain to create a unified zone out of their three occupation zones in Germany. All of these actions made each side suspicious of the other and helped lead to the Cold War.